The primary goal of this research proposal is to develop a novel approach to detect and treat lung cancers that utilizes specially engineered chitosan theranostic nanoparticles (CTNs) and uses lung-targeting Sertoli cells (SCs) to deliver nanoparticles carrying a cancer cell detecting moiety and a gene or drug to effectively treat lung cancers. Worldwide, lung cancer affects an estimated 1.3 million cases of which close to a million will die the same year. This staggering death rate exceeds the combined number of deaths from the leading types of carcinoma (breast, prostate and colon cancer), and accounts for 6% of all deaths within the US. Lung cancer patients often present with locally advanced or disseminated disease. About 6 out of 10 people with lung cancer die within 1 year of diagnosis. The major limitations have been our inability to detect cancers or remission of cancers early and the lack of drugs, which specifically treat cancer cells and not normal healthy cells. The drug delivery to the lung has been investigated using targeted nanoparticle technology that uses natural, biocompatible and biodegradable chitosan nanoparticles and short interference RNA targeting the atrialnatriuretic receptor A, a novel anti-cancer target that was designated a 'lead discovery'in oncology in 2008 for cancers. However, chitosan nanoparticles have not been used for theranostic studies. Recently, we have found that extra-testicular SCs, when loaded with nanoparticles (i.e., SNAPs) and injected intravenously into mice, travel via the circulation directly to the capillary bed of the lung where they release their nanoparticle cargo. The SNAP method increases delivery of therapeutics to the lung from the current standard of about 20% up to 90%. Together these findings have led to the hypothesize that SCs packaged with cancer cell-targeting theranostic nanoparticles comprising a near-infrared dye and siNPRA can be delivered specifically to the lung, which may provide both detection and treatment of lung cancers. To test these hypotheses, the following specific aims are proposed. Aim #1 Develop a polymer theranostics for lung cancers. In this aim, it is planned to develop strategy to develop well-defined specially engineered spherical polymeric nanoparticles (100-300nm) and deliver into lung via cell carriers for diagnostic (by in vivo imaging and MRI) and therapeutic purposes. Aim #2. Optimize and further develop a robust lung-specific delivery of Theranostic SNAPs. In this aim it is planned to optimize the delivery system by regulating intracellular expression of the enhanced green fluorescent protein (EGFP) as a reporter. The delivery efficiency, time course, dose response and persistence of gene expression in the mouse lung will be evaluated. In addition, it is proposed to evaluate the short- and long-term safety of the SNAP method by assessing the expression of SC secretory products in the lung following their delivery with or without nanoparticles. Aim #3. Test cell-targeted SNAP method in LLC1 model of lung metastasis and validate therapeutic role of siNPRA. In this study, it is proposed to evaluate the efficacy of the SNAP delivery system using cancer cell-targeted multifunctional theranostics packaged with siNPRA or psiNPRA in preventing LLC1 lung metastasis. Aim #4. Evaluate the efficacy of SNAP-iNPRA in a CC10 Cre- K-Ras-G12D model of spontaneous lung cancer. In this aim, it is planned to establish a model of spontaneous lung cancer by breeding LSL-K-ras- G12D mice with CC10- Cretg mice to generate CC10-Cre-LSL-K-ras G12D mice and to evaluate the efficacy of theranostics complexed with the inducible siNPRA or psiNPRA in suppressing spontaneous lung cancer induced by overexpression of K-ras in a mouse model. The investigators have access to all reagents and methods and have already developed necessary collaborations and feasibility studies. The results of the proposed studies are expected to validate NPRA as a therapeutic target for lung cancer and the utility of the SNAP method of gene delivery as a safe and effective approach to treat lung cancers, and set the stage for clinical trials for utilizing SNAPs to treat metastatic lung cancers.